Artificial sun-bathing enclosure



United States Patent 3,536,905 ARTIFICIAL SUN-BATHING ENCLOSURE HaroldR. Rult' and Richard J. Walsingham, London,

England, assignors to British Lighting Industries Limited, London,England Filed Sept. 7, 1967, Ser. No. 666,166 Claims priority,application Great Britain, Sept. 9, 1966, 40,447/ 66 Int. Cl. F21v 9/02US. Cl. 240-1.1 4 Claims ABSTRACT OF THE DISCLOSURE An enclosure forsimulating natural day-time illumination for sun-bathing andrecreational purposes. A ceiling coated with a material which reflectsblue light and UVB radiation from lamps within the enclosure issupported over a sun-bathing and recreation area. One or more lamps aresupported above respective windows in the ceiling and direct light downonto the sun-bathing and recreation area to simulate the suns rays.

The present invention relates to an enclosure designed to reproduce theeffects of natural conditions as closely as required for the purposessun-bathing or recreation.

It is now well known that it is mainly the UVB region of sunlight, whichis the 290 to 315 nanometer (nm.) region, which produces erthema andsun-tanning, and there are a number of beneficial biological reactionssuch as, for example, the formation of vitamin D from ergosterolsecreted under the skin. It is also well known that there are safedosage values which, if exceeded, can cause blistering or othertroubles. The acquiring of suntan by exposure to sunlight is favoured bythe majority, and in addition to natural sun-bathing, home sun lampsexist, which provide UVB at light intensities used indoors; there arealso medical UV lamps for curative medical treatments. In temperateclimates it would be advantageous if it were possible to reproducesun-bathing conditions comfortably indoors. To do this it is desirableto use less radiation intensities than the 100 watts/sq. ft. which areobtained from mid-day, midsummer sunlight.

In accordance with the present invention there is provided an enclosurehaving a matt ceiling over a base area, one or more lamps arranged todirect light downwards towards the base area to produce a visualsimulation of the suns rays, lamps arranged to illuminate the ceilingwith a difiuse bluish-white light to simulate the sky, and UVB lamps toproduce a substantially uniform distribution of UVB radiation over thebase area. The intensity of the UVB radiation is preferably controllableto suit diflerent individuals and different conditions of use.

Preferably the UVB radiation is reflected from the matt ceiling to givethe desired uniformity.

The invention will now be further described solely by way of examplewith reference to the accompanying drawing of which the sole figure is aschematic sectional view of an embodiment of the invention.

In the drawing there is shown a building 10 which houses an enclosure 11having a ceiling 12 formed by a flexible sheet of material such as acommercially available polymeric amide coated with polyvinylchloride. Abase area 13 of the enclosure 11 constitutes a sun-bathing andrecreational area and is surrounded by shops and changing rooms 14 towhich the periphery of the sheet forming the ceiling 12 is secured.

The ceiling 12 is supported by maintaining a small excess air pressurewithin the enclosure by means of air pumps 15 which pump fresh air intothe enclosure 11, air escaping from the enclosure 11 through the shopsand changing rooms 14.

Three lamps 16 for simulating the suns rays are supported on a girder 17above the ceiling 12. Each lamp 16 directs a beam of some 30 at an angleof 60 to 65 to the horizontal. A catwalk, not shown, is provided toallow access to the lamps 16. The lamps 16 are tungstenhalogen ormercury halide lamps.

Further lamps 18 are mounted above the shops and changing rooms 14 andemit blue light towards the ceiling 12.

Lamps 19 for producing UVB radiation are also mounted above the shopsand changing rooms 14 and emit radiation towards the ceiling 12. Thelamps 19 are fluorescent lamps having a special phosphor coating toconvert 253.7 nanometre radiation into UVB. For example, each lamp 19can comprise a fluorescent tube made of UVB transmitting glass such asChesterfield 085 or 046 glass, coated internally with thallium activatedcalcium phosphate or lead activated zinc barium silicate.

The ceiling 12 has a matt aluminium or aluminium oxide coating 20 whichreflects the blue light from the blue lamps 18 and the ultra-violet fromthe UVB lamps 19. Windows of transparent material are provided in theceiling 12 below the lamps 16 to allow the lamps 16 to shine through theceiling 12.

The smoothly curved surface provided by the flexible nllaterial formingthe ceiling 12 aids the illusion of a blue s y.

What is claimed is:

1. An enclosure comprising:

(a) a matt ceiling,

(b) means for supporting the ceiling over a base area,

(0) first lamp means in proximity to said ceiling and arranged to emitlight directly downwards toward the base area in simulation of the sunsrays,

((1) second lamp means below said ceiling and arranged to illuminate theceiling with diffuse bluishwhite light, white light, and

(e) a plurality of UVB lamps below said ceiling and arranged inconjunction therewith to distribute UVB radiation substantiallyuniformly over the base area.

2. An enclosure as claimed in claim 1, wherein the UVB lamps areararnged to direct UVB radiation to the ceiling.

3. An enclosure as claimed in claim 1, wherein the ceiling is formed bya sheet of flexible material, and the means for supporting the ceilinginclude means for maintaining a small excess of air pressure within theenclosure.

4. An enclosure as claimed in claim 3, wherein the first lamp meanscomprises at least one lamp supported above the said sheet, the secondlamp means comprising a plurality of blue lamps which, with the UVBlamps, are arranged within the enclosure adjacent the periphery of thesaid sheet, the periphery of the said sheet being secured to structurescomprising shops and changing rooms.

References Cited UNITED STATES PATENTS 883,944 4/1908 Fish 2401.11,324,008 12/ 1919 DHurny 2401.1 2,125,319 8/1938 Schlumbohm 240-1.12,831,966 4/1958 Porteous 240-1.1 3,152,763 10/1964 Gangbin 24 1.1

JOHN M. HORAN, Primary Examiner F. L. BRAUN, Assistant Examiner US. Cl.X.R. 2409, 51.11

